The Yellowstone "super-volcano" is a little less super -- but more active -- than previously thought. Researchers say the biggest Yellowstone eruption, which created the two-million-year-old Huckleberry Ridge deposit, was actually two different eruptions at least 6,000 years apart. Their results paint a new picture of a more active volcano than previously thought and can help recalibrate the likelihood of another big eruption in the future.